Suspension Lift info - on johnmeister.com/jeep/sj
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A Few Words On Lifting Your FSJ
Contributed By: Michael E. Shimniok
Version 2.2 03/29/2001
Submitted to johnmeister.com/jeep/sj November 2001 (links are not maintained, cut and paste)
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INTRODUCTION
One of the first modifications a lot of people make to their FSJs is a
lift kit and bigger tires, and with good reason, since this is one of the
best modifications to improve off-road performance. While standard advice
recommends lift kits only to accomodate larger tires, stock FSJs need a
lift to increase frame clearance as much as for tire clearance because
they ride lower than conventional 4x4s. Also unlike other vehicles, once
they are lifted, breakover clearance is astonishing thanks to drivetrain
components neatly tucked up into the vehicle so that they don't protrude
below the frame. If that wasn't enough reason to lift your rig, don't
forget that an FSJ with any amount of lift and bigger tires looks pretty
darn cool.
You may already know what you want. Fine. If not, ask yourself what
you'll be using the truck for now and in the anticipated future, and what
are your constraints. Some examples: price, ease of installation, ride
quality, handling, tire size desired, durability, and so on. Based on
what's most important to you, you can determine which lift options are
likely candidates. It's better to get a little bit more than you need
right now than be faced with the options of living with inadequate lift,
buying and installing another lift kit, or worse, abandoning your truck
for something taller. Just a note, most prices were collected in late
1998 but they seem to be pretty close in Fall 2000 when this was written.
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LIFT KITS
A quick note to help you make your decision. Any of these lift kits where
springs are replaced are going to require a pretty significant amount of
time and effort for the novice backyard mechanic, and is still no small
task for someone more experienced, but having done one, I know that if I
were crazy enough to want to do another, it would go much more quickly
because I've learned all the 'tricks'.
Rancho makes a 2.5" lift for around $590 total. Warranty on this is
superb; parts that are in any way failing including scuffed paint, get
replaced, no questions asked. This lift kit probably doesn't include
shocks, but Rancho makes RS5000s and RS9000s in the right size for a 2-3"
FSJ lift. More on shocks later. To date I don't know of anyone who's
installed this lift so I am unable to report on performance.
Superlift makes a 4" kit that comes with front springs, and your choice of
rear blocks only, or add-a-leafs (short or long) and rear blocks. Their
webpage now reports that you can also use "Superride Springs" in the rear
implying an all-spring kit which is good news, but you best check it out
for sure. From $390 to $450 for the spring/block combinations. Shocks are
around $170. I'm told the warranty on this is reasonably good; defective
or failing/failed parts are replaced after dealer verification. This kit
doesn't include the pitman arm (around $70) or the extended brake lines
(around $100). I've heard from a couple of people with this kit and the
ride quality is stiff according to one fellow in spite of the fact that
Superlift uses 7 springs in the front pack. On the other hand, harsh ride
may be more a function of the shocks as I'll discuss later. Also, a
"stiff ride" to one person is a "firm suspension" to another.
Skyjacker does an all-spring 4" lift "system" for around $650 as well as a
spring/block system at a lower price. This does not include shocks,
dropped pitman arm, or brake lines. Expect a total of $1000 for the
all-spring system. Skyjacker's Hydro shocks are $120 and offer a
tolerable ride while their Nitros for $140 will jar your spine. Based on
IFSJA posts from 1997-1998, this is the most popular kit by far. My
personal experience is that it outflexes Superlift and Rough Country kits,
and Black Diamond add-a-leafs on the trail, and it offers a very
comfortable ride as well. On the downside, a few IFJSA members have
reported noticible bump-steer even with the dropped pitman arm while
others have no problem. Also, while this system will realize 5-6" of lift
over sagging springs, the vehicle will sit perfectly level. Without a
slight rake, Wagoneers and narrow track Cherokees will appear to be
dragging their tails and will actually sit tail down with a load in back.
Skyjacker makes an add-a-leaf but that sacrifices flex, the only reason I
can think of to spend so much money on this system (as I did). Short
(1.5") tapered blocks to replace the tapered wedges on the spring packs
are reported to have helped in one instance.
Trailmaster does a 4" front spring, rear add-a-leaf + block for $360. You
have your choice of a long or short add-a-leaf. You can even go with just
a block lift. Prices vary a little based on the type of lift you choose.
Shocks run around $170. Dropped pitman and brake lines are not included.
I haven't found anyone with this kit so no additional information is
available.
Rough Country manufactures a 3" lift, your choice of blocks in the rear,
or a full "system" of four springs. The front springs and rear block kit
runs $325. The full "system" runs $525 at Rocky Mountain Suspension, but
can be more elsewhere. The system includes Heckethorne Hydros. Two CFSJA
club members have this kit. One reports the ride as bouncy but improving
over time, and I notice the flex off-road isn't as good as Skyjacker, but
you can't beat the price; it is the lowest of any all-spring kit that I'm
aware of.
Pro Comp (4 Wheel Parts Wholesalers) does a 4" lift and it runs pretty
cheap, also, but according to a local shop you supposedly pay for that in
terms of material and difficulty with warranty. I have since discovered
4wp has a local store here so they are a competitor to this shop. I have
also heard good things about 4wp from a couple of folks. Bottom line for
this or any lift kit, be certain that it isn't difficult to get warranty
replacements and find out if your local shop can handle this for you or if
you have to ship the items to the manufacturer directly. This would be
less an issue if they have a local storefront.
Black Diamond by Warn now makes a 4" spring lift out of front springs and
rear blocks. This is a new one since I last wrote this blurb. At least
one person bought this kit, but got helpers in rear and 2" blocks, with
a special deal from Tarheel 4x4 in Charlotte, NC. Awaiting information on
price and performance.
Big Dick's Suspension makes a 4" all-spring lift kit called "Glide Ride"
for Full Size Jeeps http://wwwbds-suspension.com/Jeep%20J10.html. It
turns out David Allen Racing sells this kit for a measly $279 (I can hardly
believe this--this is cheaper than a spring/block Rough Country setup).
Check http://davidallenracing.com/trucklifts.htm towards the bottom. The
"no fine print" warranty on the BDS lift is superb. If you're the original
owner and it breaks, you get a new part, free. Also of note, these are
military-wrap springs, meaning the 2nd leaf also wraps around the spring
eye to support the vehicle in case the main leaf breaks. I don't believe
you'll find this in any other kit on the market.
Rusty's Offroad in Alabama now offers several lift options for our beloved
rigs: http://www.rustysoffroad.com/suspFSJeep.html. They offer a 3.5-4"
kit with 4 new spring packs, shocks, brake line extenders and hardware for
$500, a 3.5-4" spring/AAL/block kit with shocks, brake line extenders and
hardware for $300 Drop pitman arms (I personally would recommend them for
over 3" lift) costs $60. Finally, they offer a 2" 4 add-a-leaf kit with
shocks for $220. The shocks are Rusty's Hydros. Though not on the
webpage, you can call about a 6" lift as well with all the extras of the
4" kit for about $700.
Another tip I received is that Tarheel 4WD Center offers a 4" lift. It
appears to be specific to this company. It was installed on a friend's
late-model Grand Wagoneer. Apparantly many FSJs have enjoyed this upgrade
in the Charlotte, NC area and the company has built a reputation in the
off-road community. You can contact them for more information at
704-598-1000. The kit consists of front spring, rear block and
add-a-leaf, and shocks, for a total of around $510 for parts. The friend
who tuned me into this says the front springs are Warn but you best just
call 'em and get the details. Then let me know.
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SAFETY
Before we do anything else, lift blocks in front are SUICIDAL. They're
A-OK in back, but in the front you'll lose the axle and likely your life.
Do NOT do this! Also, do NOT stack blocks in back. They are likely to
come apart on you and anyway, axle wrap is absurd. Use one block each
side only.
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BODY LIFT
One cheap option is a body lift (2"-3") available from JC Whitney and from
polyeurethane bushing manufacturers. Check ESPO, Energy Suspension,
Daystar, and Prothane. At least one of these carries a body lift kit.
You gain tire clearance but only minimal frame clearance (due to taller
tires) which I feel is a significant problem for a stock rig going on any
but the very easiest trails. There are other considerations with this
method, making it more complicated. You need to worry about your engine
fan in relation to the radiator. If the kit doesn't include them, you'll
need to fabricate extended linkages for the transmission and transfer
case. You may find wiring and other cables and lines a problem as well.
Bumpers and fenderwells will look goofy but this can be dealt with. You
won't have to worry about brake lines at least. You can combine this with
a suspension lift for a large total lift without the penalties or
difficulties of a very large suspension lift.
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SPRING OVER AXLE
Another option for lifting is a spring-over conversion in front which will
gain 5-6" of lift and improves articulation versus the stock spring-under
configuration. However, this is no easy task. The spring pads must be
moved on top of the axle tube in a position that maintains the proper
driveline angle. Then to correct caster, which enables you to steer
properly, the steering knuckles must be cut off and re-welded at the
proper angle. This isn't something for a backyard mechanic to try. Only
a very skilled individual who won't weaken the axles and will set up the
driveline angle properly can pull this off. I'd expect to pay at least
$1000 for this job. You might also need to look at high clearance
steering knuckles to avoid hanging up your tie rods on every rock. At
least one kit exists on the market. This isn't a DIY as a mistake can, of
course, be deadly. You'll need a mechanical engineer for the design and a
machinist for the implementation to do this right. There, you've been
warned.
A cheaper alternative is to find a full size Ford or Chevy front axle.
Check the measurements on their spring pads to see if they match width
with your springs. They probably will. You can then set about figuring
out how to change the Chevy/Ford steering system to the Jeep system or
vice versa. The Chevy system appears to be inherently immune to bump
steer so that might be the best bet. As for the rear axle, well, you'll
probably want to go with a full-size rear too, since they are several
inches wider than even a Jeep widetrack axle. Look for Dodge rear axles
which are reported to be a good fit. Find a Dana 60 on vans and some
pickups. You'll want to add 6" or more of lift out back, preferably with
a combination of springs and blocks or maybe custom springs only (more
expensive). These wider axles especially when combined with the 35" or
bigger tires you'll want will introduce clearance issues so be prepared
to do some major trimming. Once again, measure, because these reports
of big-3 axles fitting FSJs without much effort is second-hand. Just
spend a day in a good junkyard and measure the distances between the
spring pads of various axles.
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CUSTOM SPRINGS
You can have springs fabricated. National Spring (in CA) is one company
that is well known in this area. You might check into ESPO as well
(http://www.espo.com). Apparantly National does a fabulous job, tailoring
the springs to your vehicle's weight and your requirements of lift,
carrying capacity, and whatnot. Their springs can be pretty expensive
though. The springs and bushings alone exceed the cost of the entire
Skyjacker system shipped to your door. Obviously you'll still need
shocks, dropped pitman arm if you're going 4" or more, and brake lines,
then you'll have to ship all this heavy stuff.
Alcan Spring (http://www.alcanspring.com) in Colorado also builds custom
springs built to your vehicle weight and specifications. This great tip
came in from Andrew D. (rockjeep44@hotmail.com). They have been building
springs since 1982 for a variety of applications. Andrew says these
springs have been flexed hard off-road without any sag so far and he says
that they are very, very flexy. His rig is equipped with spring-over in
front and revolver shackles both of which make a drastic improvement to
articulation, which makes it hard to compare the springs to others. But I
think it is pretty likely that they can build you springs that ride better
and flex more than Skyjackers for around the same price. Andrew says
their price is around $300-400 per axle. One thing is certain, Andrews'
combination of spring-over and revolvers is guaranteed to get you about as
much flex as you will get out of an FSJ without using coil springs. On
top of everything else, he says the ride quality is good, too!
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SPRING REARCHING
One inexpensive option is to have the stock springs rearched, which costs
between $200 and $400 for all four springs. The disadvantage of rearching
a set of stock springs to be higher than stock is a potentially rough
ride, though the one truck I drove with rearched springs didn't seem too
bad. Softer shocks may be the reason. Off-road performance seems quite
acceptable from what I've seen. There have been reports of rearch jobs
sagging prematurely, though that probably depends on the shop and the type
of springs you had originally. Ask around for a very good specialty
spring shop. There is undoubtedly a reasonable limit to rearch height.
Since the springs aren't changing length, they are being set at a higher
ride height than stock, so you gain compression travel (in theory) and
lose droop travel. You have to limit rearch height because at some point
you won't have enough spring droop to travel down the highway safely.
You better ask a shop but seems to me you would want to use stock shocks,
since the actual spring travel doesn't increase.
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ADD-A-LEAFS AND BLOCKS
For under $200 you can get a 2" lift by purchasing Black Diamond
add-a-leafs from Warn, a set of generic lift blocks (slight taper might be
best here, ask a 4x4 shop for advice), and u-bolts which you can have
custom manufactured for $10-20 each. Big Dick's Suspension also builds
add-a-leafs for FSJs, but the price and resulting amount of lift is
unclear on their website. http://www.bds-suspension.com/addaleaf.htm.
The setup is easier to install than new springs. The ride is harsh, but
at least you'll be able to fit 31" tires, more or less. You can also find
add-a-leafs for the rear which makes for a much harsher than stock ride.
They are probably more expensive than blocks. You eliminate associated
axle-wrap problems, however. In theory, add-a-leafs do not offer as much
suspension travel as stock or aftermarket spring-only systems which is
verified by my own experience. By adding an extra piece of spring steel,
especially one designed to increase spring pack arch, your spring rate
(stiffness) increases as well. Lower spring rates flex off-road more than
higher spring rates. Stock length shocks should be more than adequate for
add-a-leafs because spring travel is not increased with add-a-leafs.
This also saves you some significant money over new spring packs.
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SHACKLE CONVERSIONS
Extreme shackle conversions of more than 1-2" are a big safety no-no
especially up front. Generally this isn't an issue since there are no
known aftermarket shackles for FSJs as there are for baby Jeeps. A number
of FSJ owners have been exploring different options. A shackle reversal
up front moves the shackle from the front of the spring to the rear.
This affects caster and driveline angle which must be corrected. It does
gain you 1-2" of additional lift.
If you were to adapt slightly longer shackles at the rear of the front
spring, you would not pay the approach angle penalty associated with
shackle extension up front. You might take a ruler to a junkyard and see
what shackles and shackle housings can be swapped over to an FSJ, which
might open the door to better, longer shackles, but again be sure to
compensate for caster.
In the rear, some folks have discussed what I'll call a shackle flip,
where you cut off the box holding the rear shackle and flip it upside
down, so that the shackle is no longer pointing up, but pointing down.
You really ought to know what you're doing and think this through
carefully before trying it. However, this should give you a bit of lift
while simultaneously compensating for driveline angle, and should also
increase overall articulation, as the shackle is now free to move through
a much wider arc whereas in stock form its travel is limited by the box.
As alluded to above, apparently Revolver Shackles can be adopted for use
with FSJs, at least up front. I am researching the details currently.
Meanwhile, check TeraFlex http://www.teraflx.com/ which sells these for
about $185-220 a pair. When fully extended you get an extra 10" of droop
without any sacrifices on the highway. Revolvers would only work out back
on a rig with a shackle flip.
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LOCKERS VERSUS FLEX
Last thing to remember is that a locker can make up for a stiff suspension
any day, and there are some inexpensive, sturdy ones available. However,
it won't make up for body and frame clearance. Ask me how I know.
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SHOCKS
A number of shocks are available. I've listed most of them along with the
kits above. Without qualification I would recommend Rancho RS9000s for
any application because they offer adjustable ride quality and have been
known to significantly improve ride quality on-road even on my 85 with
add-a-leaves without losing off-road control. They are spendy at $240 but
I feel they are well worth the extra money. Rancho occasionally has "buy
3 get one free" sales which make them competitive with non-adjustable
shocks. Forget RS5000s as I hear they are pretty stiff on FSJs which
seems to also be true of gas shocks. Edlebrock and Bilstein both make
'smart' shocks that use valving to react differently to different kind of
bumps and hence different driving conditions. One or both of these may be
available for FSJs in different lift sizes.
The trick with RS9000s and others is getting the right size if the shocks
come with the right eyelets in the first place. Rancho makes shocks
recommended for FSJs in a 2-3" lift size. For a 2-2.5" lift, use this
size. For a 3" or above lift, find out the extension and compression size
on the shocks that ship with the kit, then get the nearest match in the
brand you want. Your 4x4 shop can help you with this. I chose a set that
offered a couple of extra inches of extension and a little less (fractions
of an inch less) compression which is ok because on a 4" lift your
springs won't be able to compress anywhere close to the bumpstops anyway.
Best bet is to ramp the truck with shocks disconnected and measure travel
and add a few inches for fudge but this easier method works fine.
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TIRE FITMENT
Without going into all the details, let me try to answer the question of
what tires fit with what lift sizes. This is for off-road where
articulation stuffs the tires into the wheelwells something fierce. It
depends partly on the lift kit itself but also on wheel width, tire width,
and body style. If you have a widetrack Cherokee or a J-truck with
flares, you have it easier. With such huge fender openings, you can
probably fit 32x11.50" tires stock, bigger if you trim your fender flares.
With a 4" lift, you can probably fit 33x12.50" tires with no contact, and
35x12.50" tires with a bit of flare trimming. I suspect that with
aggressive flare trimming, 35's are within reach with only 4" of lift,
certainly enough to make the narrowtrack crowd envious!
Narrowtrack vehicles will need a 2" lift for 31x10.50" tires and minimum
4" lift for 33x12.50" tires if you choose stock or 8" rims. These aren't
hard and fast values. For 33x12.50" tires rear fender triming is in
order. With some trimming front and back, the Rough Country 3" kit will
fit 33's. A 4" kit with 10" wheels and 33's will need trimming especially
the top of the rear fender. All of these rules of thumb depend heavily on
how much your springs flex, the true height and width of your tires versus
the size stamped on the sidewall, and more.
Your best bet is to fit up the tires and ramp the truck and see where it
rubs. If you pound in the forward lip of the rear fender and grind the
rocker/quarter seam to match, you can fit 31's on a saggy rig, rearch or
add-a-leaf setup. They'll rub but they won't get chewed up. This may
also allow you to safely run bigger than normal tires with a lift without
trimming but I doubt it because that opening is pretty narrow! Lastly,
you can cheat by going with narrow tires, sacrificing stability and
traction. Check into 33x9.50" or 33x10.50" tires, new as of 2000. But
the diameter of the tire versus the narrow rear fender opening is still
likely to cause trouble. Going beyond 33's in a narrowtrack is a
challenge. Look to body lifts and fender trimming first then get creative
if that doesn't help. Of course there are other issues to address with
bigger tires such as reduced braking performance, increased strain on
axleshafts, steering components, etc. To do it right, research and
careful thinking is in order.
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BUSHINGS
A quick note on bushings. It seems that all the kits include full
bushings for any component being replaced (ie: front spring bushings if
replacing front springs) which means you may want to upgrade your sway bar
bushings. Good luck. Same goes for shackle bushings. You might check
your dealer for those, however FSJ dealer stock is running out and
Daimler-Chrysler is not going to keep manufacturing old parts. I couldn't
find a single place on the web that manufactured poly front shackle
bushings. However, for other bushings, check ESPO, Energy, and Prothane.
Some day it will be necessary to attempt to measure and try to find the
closest matches. Meanwhile write to these manufacturers and complain
about their limited FSJ selection. Eventually one of them will realize
there's a market for these parts.
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LIFT ISSUES
As lift increases, so does cost, and other factors. It's always best to
consider the whole vehicle when lifting rather than trying to cut corners
and ending up with something unsafe, unreliable, or weak. Consider the
following issues, then refer to the quick guideline at the end of this
section.
Trac Bars and Sway Bars
With lifts over 2" you'll need to detach and remove front and rear trac
bars (late model linkage that limits minor sideways axle movement) and
you'll have to disconnect your sway bar end links if you have a sway bar.
Will this be unsafe? Given the millions of FSJs that rolled off the
assembly lines of the '70's with neither trac bars nor sway bars, I would
have to say, no. Body lean will increase around corners without the sway
bar and steering turn-in will be slower and perhaps more steering input
will be required to turn. You shouldn't be driving your FSJ like a sports
car before or after a lift, and you should be conservative driving it
around corners anyway. If you like taking fast corners, buy a sports car
and join the SCCA so you can partake in Solo II racing.
If you want to keep your sway bar functional, you can replace your sway
bar end links with quick disconnect end links from JKS or Warrior (around
$70) in the correct length for your lift. Ask for the Wrangler model in
the lift size you have on your truck. The JKS models offer better
construction but disconnect from only one end. They come with grease
fittings, greasable fluted poly bushings, and stainless steel parts (from
the advert). The Warriors work fine and the center section can be
completely removed so there's nothing to tie up out of the way.
Track Width
As you increase your lift, you want to increase your track width either by
increasing tire, wheel, and/or axle width, to maintain stability. Don't
be like some of those Ford Explorer owners who lift their rigs 4", and
mount 33x9.50" pizza cutters to 7" stock rims on ultra narrow axles. Not
only does it look silly, it is less safe than the stock setup.
Bump Steer and Pitman Arms
At 3-4" of lift, you will need a dropped pitman arm (around $50-80 from
most lift kit manufacturers above), which corrects the geometry of the
drag link and tie rod. The alternative is bump steer. Hit a bump and you
change lanes. This is bad. (I didn't need to tell you that, did I?)
Brake Lines
You don't want to flex so much you yank off a brake line as you're
pointing down a steep slope, do you? Well, there's a solution that runs
under $100: stainless steel brake lines. They also improve braking by
reducing brake line expansion versus rubber lines.
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TIRE ISSUES
You're getting a bigger lift for bigger tires, among other things, so
again you should consider the whole operation, not just the lift
kit. There are a number of safety issues related to tires.
Brakes
With big tires, your vehicle won't stop as quickly! You may argue that
the contact patch of the tire increases giving you more traction. That
isn't the issue. At issue is that FSJ brakes are lousy by modern
standards and whereas it is a rare FSJ that can stop quickly in stock
configuration, when you start adding weight to the wheels in the form of
bigger tires, steel wheels, etc, your rolling mass gets outrageous. The
brakes aren't up to the task of slowing down that much rolling mass. You
can do a few things to improve braking including Raybestos top-of-the-line
brake pads combined with Valvoline synthetic (NOT SILICONE) brake fluid,
regularly flushing and bleeding your brake system, and replacing any
faulty equipment. I honestly would feel uncomfortable using stock 3/4 ton
FSJ disc front, drum rear brakes with 35" tires. Simply choosing a
lighter tire or lighter wheels will help, not just with braking but with
acceleration.
Shocks
For the same reason that the vehicle won't start or stop as easily, your
shocks will be less effective as your tires get heavier. The thing is, as
they weigh more it takes more force to resist their movement. Stiffer
shocks will probably get you into some pretty big tires. My only
experience was a puzzling event in which my RS9000's were set to 2, sway
bar disconnected, 31" tires hit a bump and started oscillating. I don't
have this problem with the shocks set to 3. I believe RS9000's at 3 are
probably less stiff than some aftermarket non-adjustable shocks. Anyway,
how big can you go? I have no clue. I would think once you get into
35" tires you might need to look into stiffer shocks, once you get really
huge, dual shocks might be worth considering.
Axle Gearing
When you increase tire diameter you're increasing the effective final
gearing of your vehicle. In other words, running a vehicle with 3.31:1
differential gears and 31" tires is the equivalent final gearing of a rig
with stock tires and 2.9:1 differential gearing. The highest FSJ gearing
known is 2.72:1 in many 80's FSJs. I would not recommend exceeding stock
size tires with this gearing. The lowest Wagoneer gearing in the 80's is
generally 3.31:1, with J-trucks often running even lower gears. I would
not recommend exceeding 31" tires with 3.31 gears. In the 70's most
Wagoneers had 3.54 gears which would support 33" tires. If you get 3.73's
or lower you can run 33-35" tires. When you add this larger, heavier
tires you will seriously lose performance. Axle regearing is the best
solution but it is expensive. If you can swap in higher geared
differentials cheaply, do it. You'd better plan ahead on your ultimate
tire size so you can get the gearing right. Check out http://www.4lo.com/
for calculators online that will help you make the right choices.
Driveline Strength
Once you get into 33" tires you're probably at the borderline of the
engineering limits of your FSJ's driveline, give or take. I'm talking
about off-road use, not street use. Driving style, the types of trails
you use, whether you have lockers or not, and many other factors determine
how often you'll break. FSJs are strong, far stronger than many baby
Jeeps. But those Dana 44 or AMC 20 rear ends probably won't hold up to
very large tires on very hard trails. The driveshafts may also give out.
So consider heavy duty driveshafts, front and rear axles, ring and pinion
sets, axleshafts, ujoints and more. If it breaks once, consider
upgrading. The 4x4 rags have a lot of tips on improving driveline
strength. Other options include upgrading yokes to larger u-joints, axle
trusses, hub fuses (intentionally weak cheap hubs so they break instead of
your axle, check Warn), and more.
Steering Stabilizer
A quality steering stabilizer might be a good idea. Those set you back
anywhere in the $35-$50 range. Rancho, Superlift, Heckethorne and
presumably others manufacture drop in replacements for our rigs. You'll
want a single stabilizer. Duals are for huge tires like above 35".
While you're at it make sure your steering is in good shape. With bad
ball joints, drag link ends, tie rod ends, and/or steering box, keeping
your rig travelling in a straight line is hard enough, but when you add a
lift and big meats this task turns into a holy nightmare. I spent a
fortune on my rig's front-end, but it now steers like a sports car.
Steering System Strength
Pushing around 235/75R15's is no sweat for the stock system which is
pretty darned strong. I wouldn't be surprised if you never have trouble
off-road with 33" tires and a stock system. It is probably overengineered
quite a bit. If you start bending tie rods, drag links, or going through
steering boxes or pumps, you might consider upgrades. I don't know
specifically of any aftermarket forged or high-quality steel tie rods or
drag links, but look around. AGR is well known for heavy duty steering
boxes and pumps, to be used in combination, and FSJ versions are
available. They are spendy, though. It'd take quite a few failures to
pay for the set.
Spare
You can fit a 31" spare under the bed of a Wagoneer with a little trimming
of tabs and if you don't have a hitch that interferes. If you have a
body-mounted tire carrier, a 31" tire on steel wheel will live back there
for a long time with no problems even with off-road abuse. I would be
worried about anything heavier than this if you also carry a full five
gallon jerry can on the carrier. I plan on using a 33x9.50" spare mounted
on a light aluminum wheel when I upgrade to 33's. There are no narrow
35" tires, so at this point your only option is roof mounted (on a roof
rack designed to support this kind of weight) or a frame-mounted tire
carrier.
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QUICK GUIDE
This is a guideline, not the definitive answer collection. Much of the
following is, quite honestly, my best stab based on what I've read in
magazines and the mailing list. Use your noggin when you're lifting so
you make sure you cover all the bases, and talk to mechanics, 4x4 shops,
mailing lists and more. This document will give you a lot of information
to get started, but all the responsibility to do your lift safely and
correctly is yours!
Lift Guide
4"+ Expensive unless you combine body & suspension lifts. Consider all
the issues above.
4" Consider all the lift issues above
3" Shocks, extended brake lines, disconnect trac bars & sway bars,
pitman arm may be optional, track width.
2.5" Shocks, maybe extended brake lines but check first, trac bars, sway
bars, track width.
Tire Guide
35"+ Consider all the tire issues
33" Brakes, steering stabilizer, spare, perhaps other tire issues above.
32" Brakes, spare, maybe other tire issues.
31" Brakes, though not as critical
30" I doubt you need to change anything for a 1" bigger tire.
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COMPARISONS
I still have no RTI number comparisons which would be extremely useful.
If you have RTI figures, email me and state the score, the type of ramp
(20, 28, 30 degrees), your lift kit, the type of truck you have (important
for wheelbase comparison), shocks and their sizes, and any other
modifications to your lift, suspension, and axles.
As you gathered, I installed a 4" Skyjacker lift on my 86 Grand Wagoneer,
"Troubled Child" and am more than pleased. I am running 31x10.50" tires
but will be upgrading to 33x12.50" tires and wider axles at some point
soon. I plan to install lift blocks to compensate for tail dragging and
clearance. Shouldn't have to but what can you do? I spent a long time
researching available options and felt most comfortable with the
configuration I chose. I would recommend it with a few caveats. I have
held my own with that Land Rover Defender 90 not to mention a few other
rigs on the trail. You will be amazed at the improvement a good lift and
tires can do for you off-road.
Michael
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JohnMeister.com
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